CVS difference for acs/ac-00153.txt

Differences between 1.1 and version 1.2
Log of other versions for file acs/ac-00153.txt

--- acs/ac-00153.txt	2007/12/07 02:38:57	1.1
+++ acs/ac-00153.txt	2007/12/13 04:40:40	1.2
@@ -327,3 +327,101 @@
 somewhere.
 
 ****************************************************************
+
+From: Adam Beneschan
+Sent: Friday, December 7, 2007  11:45 AM
+
+> It is clear from the discussion (and rejection!) of AI05-0068-1/01 at
+> Fairfax that in Legality Rules, "object" and "type" always really mean "view
+> of object" and "view of type". Anything else would break privacy and cause
+> all manner of bad effects.
+
+I'd like to make a couple points in this regard:
+
+(1) The original sentence that caused me confusion (3.10.2(12.4)) was
+    in a "Static Semantics" section, not a "Legality Rules".  Perhaps
+    what you're saying applies to both.
+
+(2) With regards to this suggestion:
+
+    "When it is clear from context, the term *object* is used in place
+    of *view of an object*. Similarly, the term *type" is used in
+    place of "view of a type"."
+
+    I think I could live with something like this anywhere in the RM
+    *except* 3.10.2 (maybe there's a few other places).  One reason is
+    simply that 3.10.2 is so difficult (for me) to understand that
+    when I read it, I try read it very carefully to make sure I'm
+    getting it right; and I tend to go more into my "take everything
+    literally" mode, or perhaps you could call it "fine-toothed comb"
+    mode, to make sure I understand what's going on.  Simply because
+    of that, from my point of view this is probably the wrong section
+    of the RM to rely on things being "clear from context".  Another
+    particular issue with 3.10.2 is that 3.10.2(5), which introduces
+    the section I had the problem with, says:
+
+    "Each master, and each entity and view created by it, has an
+    accessibility level:"
+
+    Since an object is an entity, this would seem to say that
+    *objects* per se have their own accessibility levels, and the view
+    of an object would have its own accessibility level---and the two
+    don't necessarily match.  This introductory sentence suggests, by
+    itself, that in this section, it should never be assumed that
+    "object" means "view of an object".
+
+So even if it's decided that it's too much work to make all the
+wording precise everywhere in the RM, I'd like to suggest that 3.10.2,
+or at least paragraphs 5-22, do need to be precise, and not rely on
+anything being "clear from context".
+
+****************************************************************
+
+From: Randy Brukardt
+Sent: Friday, December 7, 2007  11:01 PM
+
+> (1) The original sentence that caused me confusion (3.10.2(12.4)) was
+>     in a "Static Semantics" section, not a "Legality Rules".  Perhaps
+>     what you're saying applies to both.
+
+The AARM note that I proposed said exactly that.
+
+> (2) With regards to this suggestion:
+>
+>     "When it is clear from context, the term *object* is used in place
+>     of *view of an object*. Similarly, the term *type" is used in
+>     place of "view of a type"."
+>
+>     I think I could live with something like this anywhere in the RM
+>     *except* 3.10.2 (maybe there's a few other places).
+...
+> So even if it's decided that it's too much work to make all the
+> wording precise everywhere in the RM, I'd like to suggest that 3.10.2,
+> or at least paragraphs 5-22, do need to be precise, and not rely on
+> anything being "clear from context".
+
+I personally think that it is *hardly ever* clear from context, and that any
+wording that confuses anyone reasonably knowledgeable with the Standard should
+be made explicit. (That certainly was true of 3.9.3(4/2), since neither Pascal
+nor I realized it was "obvious" that that rule applied to views of types rather
+than just types. You get nonsense results otherwise, but it takes a while to
+figure that out, and surely that shouldn't be a criteria for determining
+wording. But the full ARG felt otherwise.)
+
+But I've tilted at that particular windmill a number of times, and I don't
+think it makes sense to waste any more of my time (or the ARA's money)
+continuing to do so. Unless you can convince other ARG members (who come to
+meetings!!) of the need for a wording change, there is no point in progressing
+your request.
+
+What bothers me is that the Standard has no indication that you might need to
+stick "view of" in front of various entities in rules. I don't know how you are
+supposed to read that into the current wording of the Standard, whether or not
+it is "clear from context" (which is a point that always can be argued).
+Depending on the "font of Ada intent" (that is Tucker) is not a good plan for a
+Standard!!
+
+Unless this is corrected, most wording that doesn't have "view of" is wrong.
+And thus needs to be fixed.
+
+****************************************************************

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